Stabilized extreme pressure lubricants



Patented June 13;}19 50 I Jack s. meat, Tarentum, Pa.,

rail-issue's 1 dito Gulf Research & Development Comp, Pittsburgh,

Pa a corporation of Delaware No Drawing.

i This invention relates to improved oil composi tions and more particularlyto stabilizedextreme Pressure lubricants.

Extreme pressure lubricants are employed for lubricating bearings and gears operating under high pressures. They are also employed to carry off excess heat generated and to lessen the friction created during metal cutting operations; While plain mineral oils are satisfactory for. removing heat during severe cutting operations, they do not have a sufflciently high film strength for the maintaining or a lubricating film between the tool, die or roll and-the metal being processed, nor do they have a sufiiciently high film strength to prevent seizure and scoring of metallic surfaces movably contacting each other under Application November Serial No. 186,151

6 Claims. (Cl. 252- 33) amount and the naturei the extreme pressure' agent contained in the lubricant.

In addition to the extreme pressure agent and the triethanolamine salt of the oil soluble petrochlorinated wax and naphthalene and a con extreme pressures. The film strength or load carrying capacity of plain mineral oils has been enhanced by the addition of various extreme pressure agents containing either a halogen or sulfur, or mixtures thereof. Although oils containing, extreme pressure agents such as these have good load carrying characteristics, they have a serious disadvantage in that a halogen or sulfur in oils .lead to the formation of a stain on ferrous and non-ferrous alloys. Furthermore, in the presence of moisture, ferrous and nonferrous alloys become severely corroded when contacted with an oil composition containing a halogen or sulfur.

It is an object achieved by this invention to provide an improved extreme pressure lubricant densation product of chlorinated wax and phenol followed by. further condensation of this reaction product with organic acids; detergents-such germanium oxide "condensation products.

7 In preparing-the stabilized'extreme pressure I lubricants in accordance withmy invention, the

which efiectively inhibits the staining and/orcorrosion of ferrous and non-ferrous alloys.

It is a further object achieved by this invention to provide an improved extreme pressure lubricant in which corrosive properties of the extreme pressure lubricant are inhibited without deleteriously modifying the desirable properties of the extreme pressure lubricant.

I have found that a lubricant containing an extreme pressure agentnormally tending to corrode ferrous and non-ferrous alloyscan be made triethanolamine salt of the oil' soluble petroleum sulfonic acids may be incorporated in the extreme pressure lubricant, according to several em triethanolamine salt may be produced directly in the extremepressure lubricant by separately adding triethanolamine and-.the-oil soluble pe- -troleum sulfonic acids. According to another embodiment, oil concentrates containing relatively. high concentrations of the triethanolamine salt of the oil soluble petroleum sulfonic acids may be first prepared and the desired concentration obtained in the extreme pressure lubricant solved in the extreme lubricant.

In preparing the-triethanolamine salt of the ensemble petroleum sulfonic acidsjfor use in accordance with my invention, I prefer to employ the oil soluble petroleum sulfonic acids generally referred to as mahogany acids.

produced during the-acid refining of petroleum distillates with sulfuric acid. There are two general methods employed in recovering the ma- Jhogany, acids.

lectively removing the acids by\ adsorbents or by,

The first methpd involves sesolvents such as the lower mono-basic alcohols.

The second method involves salting out the acids with iaorganicsalts or bases. These methods are x These acids.) together with the water soluble green acids, are

well-known and have been described in detail by Carleton Ellis on page 1070 of volume 2 of The Chemistry of Petroleum Derivatives. Reinhold Publishing Corporation, New York, 1937 (second printing 1945). The particular petroleum sulfonic acids used in preparing the triethanolamine salt in accordance with the procedure hereinafter set forth were obtained by acidifying an equeous suspension of the sodium salt of the oil soluble petroleum sulfonic acids with hydrogen chloride and subsequentl extracting the acids with a, suitable solvent such as ethyl ether. The average molecular weight of these acids was about 400 as determined by the neutralization equivalent.

The triethanolamine salt of the oil soluble petroleum sulfonlc acids in the tests hereinafter described consisted of an oil concentrate of the triethanolamine salt of the oil soluble petroleum sulfonic acids and was obtained by the following procedure:

50 grams of a 50/50 mixture of mineral oil and oil soluble petroleum sulfonic acids and 9.2 grams of triethanolamine, each at room temperature, were placed in a reaction vessel. The contents of the reaction vessel were then stirred for about an hour. The reaction which takes place is an exothermic reaction so that the temperature of the contents of the reaction vessel rose to about 135 to 140 F. during the reaction period. The reaction mass was a dark brown viscous material about the consistency of a medium petrolatum. The reaction mass consisted of an oil concentrate containing about 60 per cent by weight of the triethanolamine salt of the oil soluble petroleum sulfonic acids.

In the practice of my invention any suitable lubricating oil base, whether it be derived from a paramnic, naphthenic, or mixed base crude, may be employed. The extreme pressure lubriagents may be mentioned the chlorinated derivatives of paramn wax, kerosene, aromatic petroleum fractions, and coal tar solvents (naphthalene I tetrachloride) A chlorine-containing extreme pressure agent is ordinarily employed in an amount sufficient to produce a chlorine content in the extreme pressure lubricant between about 1 and about 10 per cent by weight. Thus, when an extreme pressure agent containing per cent of chlorine is used, the agent may be employed in the oil in an amount between about 2.5 and 25 per cent by weight.

The advantages to be obtained by the use of the triethanolamine salt of the oil soluble petroleum sulfonic acids according to my invention are illustrated in the following specific tests:

In these tests a highly refined light naphthenic Texas oil of 100 S. U.-V. at 100 F. and No. 2 N. P. A. color having a gravity of 24 A. P. I. was used. The effect of a sample of this oil containing 10 per cent by weight of a chlorinated liquid hydrocarbon containing about 40 per cent by weight of chlorine on polished hot rolled B. A. E. 1020 steel strips 8" x 56'' x V," in the presence of and in the absence of distilled water was compared with the eifect of another sample containing 10 percent by weight of a chlorinated liquid hydrocarbon containing about 40 per cent by weight of chlorine and 0.5 per cent by weight of an oil concentrate containing 60 per cent by weight of the triethanolamine salt of the oil soluble petroleum sulfonic acids.

In carrying out these tests, the hot rolled steel strips were half immersed in the respective oil samples in separate glass containers. The oil samples were maintained at a temperature of 122 F. In the following table there are shown the compositions tested and a comparison of the respective results showing the number of-hours before corrosion began to occur.

With 5'7 Distilled Without Water s gg' ofi'l ll 107 Chlorinated h dr (407 Slightstainaiferfl 8e t aft 4-5 eras o y cent 11 vere rus er B a o hours,@l22F. homs,@122F.

amp 0.

89.5% lib/2 Texasoil 10% Chlorinated hydrocarbon (40% No rust after 92 No rust after 92 hours.

chlorine), 0.5% Oil concentrate of the triethanolamine hours, 0 122 F. 6 122 F.

salt of the oil soluble petroleum sullonic acids (00% triethanolamine salt).

cant to which the triethanolamine salt oi the oil soluble petroleum sulfonic acids, according to my invention, may be added may be prepared by incorporating into a lubricating oil having a viscosity between the approximate limits of 50 S. U. S. and 1200 S. U. S. at 100 1''. an extreme pressure agent containing a halogen or sulfur, or mixtures thereof. The extreme pressure agent is added to the lubricating oil in an amount sumcient to impart extreme pressure characteristics and normally to impart corrosive properties. This amount may vary between 1 and 25 per cent by weight, but in any particular case the amount employed depends upon the severity of the conditions under which the oil is to be used, and upon the amount of halogen or sulfur in the extreme pressure agent. Generally the amount of halogen or sulfur in an extreme pressure compound is between the approximate limits of 5 and 75 per cent.

My invention is particularly applicable to extreme pressure lubricants containing corrosive chlorine compounds, such as chlorinated aliphatic or aromatic hydrocarbons. Among the more common chlorinated extreme pressure The data given in the table demonstrate the remarkable effect obtained when 0.5 per cent of an oil concentrate of the triethanolamine salt of the oil soluble petroleum sulfonic acids is added to a normally-corrosive extreme pressure lubricant. In sample No. 1, it will be noted that slight stain appeared on the steel strip even in the absence of water after immersion in the oil for 72 hours. It will be further noted that severe rusting occurred after only 4 to 5 hours immersion in the oil in the presence of 5 per cent distilled water. When only 0.5 per cent by weight of the oil concentrate of the triethanolamine salt of the oil soluble petroleum sulfonic acids was incorporated in the oil, in accordance with sample No. 2, no rusting occurred after 92 hours either in the presence of or in the absence of water.

While my invention has been described above with reference to various specific examples and embodiments, it will be understood that the invention is not limited to the illustrated examples and embodiments and may be variously practiced within the scope of the following claims.

I therefore claim:

1. A stabilized extreme pressure lubricant consisting predominantly of a lubricating oil, an extreme pressure agent consisting of a halogenated hydrocarbon in an amount suflicient to impart extreme pressure characteristics and normally to impart corrosive properties, and a small amount, suiiicient to inhibit said corrosive properties, of the triethanolamine salt of the oil soluble petroleum sulfonic acids.

2. A stabilized extreme pressure lubricant consisting predominantly of a lubricating oil, an extreme pressure agent consisting of a chlorinated hydrocarbon in an amount sufiicient to impart extreme pressure characteristics and normally to impart corrosive properties, and a small amount, sufiicient to inhibit said corrosive properties, of the triethanolamine salt of the oil so!- uble petroleum sulfonic acids.

3. A stabilized extreme pressure lubricant ccn= sisting predominantly of a lubricating oil, 1 to 25 per cent by weight of an extreme pressure agent consisting of a chlorinated and about 0.05 to about 1.0 per cent by weight of the triethanolamine salt of the oil soluble petroleum sulr'onic acids.

4. A stabilized extreme pressure lubricant consisting predominantly of a lubricating oil, an ex= treme pressure agent consisting of a chlorinated hydrocarbon in an amount sumoient to produce a chlorine content in the extreme pressure inbricant between about 1 and about per t by weight, and about 0.05 to about 1.0 per cent by weight of the triethanolamine salt of the oil soluble petroleum sulfonic acids.

5. A stabilized extreme pressure lubricant con sisting of about 74 to 97.5 per cent by weight of a lubricating oil, about 2.5 to per cent by weight of a chlorinated hydrocarbon containing about per cent chlorine, and about 0.05 to about 1.0 per cent by weight of the triethanolamine salt of the'oil soluble petroleum sulfonic acids.

6. A stabilized extreme pressure lubricant consisting of 89.5 per cent by weight of a lubricating oil, 10 per cent by weight of a chlorinated hydrocarbon containing about 40 per cent of chlorine, and 0.5 per cent by weight of an oil concentrate containing about per cent by weight cf-the triethanolamine salt of the oil soluble petroleum sulfonic acids.

JACK B.

The following references are of record in the :file of this patent: 

1. A STABILIZED EXTREME PRESSURE LUBRICANT CONSISTING PREDOMINANTLY OF A LUBRICATING OIL, AN EXTREME PRESSURE AGENT CONSISTING OF A HALOGENATED HYDROCARBON IN AN AMOUNT SUFFICIENT TO IMPART EXTREME PRESSURE CHARACTERISTICS AND NORMALLY TO IMPART CORROSIVE PROPERTIES, AND A SMALL AMOUNT, SUFFICIENT TO INHIBIT SAID CORROSIVE PROPERTIES, OF THE TRIETHANOLAMINE SALT OF THE OIL SOLUBLE PETROLEUM SULFONIC ACIDS. 